Re: SetMode(Enum) vs. SetModeA(), SetModeB()...
jehugaleahsa@gmail.com ha scritto:
struct Marker
{
virtual ~Marker() = 0;
};
struct ModeA : Marker
{
virual ~ModeA() {}
};
struct ModeB: Marker
{
virtual ~ModeB() {}
};
. . .
void setMode(Mode mode) {} // guaruntees a mode - can use overloading
to prevent dynamic casting - plain Mode won't compile since it is
abstract.
What is "Mode"? Is the same as "Marker"?
. . .
setMode((ModeA));
As always, I never test my code before I post, so you may or may not
need the extra set of parens. Also, try a const& if that doesn't work
either.
(well... you should consider testing your code before posting...)
The extra set of parenthesis won't make any difference, the code is
essentially broken anyway. ModeA is a *type* and you can't pass types as
function parameters. You may thing of using ModeA() instead, which would
pass an instance, but it wouldn't work either because you would incur in
"slicing" (http://en.wikipedia.org/wiki/Slicing).
There are several ways to implement the State pattern and I'm not going
to discuss them here, there are plenty of books and online references on
the subject and it's beyond the OP's original question.
Regards,
Ganesh
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